Updated JuliaSet demo. Did not work with the new shader version.

Examples/Shaders/JuliaSet.cs

@@ -41,6 +41,10 @@ public class JuliaSet
         //--------------------------------------------------------------------------------------
         const int screenWidth = 800;
         const int screenHeight = 450;
+        const float zoomSpeed = 1.01f;
+        const float offsetSpeedMul = 2.0f;
+
+        const float startingZoom = 0.75f;
 
         InitWindow(screenWidth, screenHeight, "raylib [shaders] example - julia sets");
 
@@ -48,14 +52,15 @@ public class JuliaSet
         // NOTE: Defining 0 (NULL) for vertex shader forces usage of internal default vertex shader
         Shader shader = LoadShader(null, $"resources/shaders/glsl{GlslVersion}/julia_set.fs");
 
+        // Create a RenderTexture2D to be used for render to texture
+        RenderTexture2D target = LoadRenderTexture(screenWidth, screenHeight);
+
         // c constant to use in z^2 + c
         float[] c = { PointsOfInterest[0][0], PointsOfInterest[0][1] };
 
         // Offset and zoom to draw the julia set at. (centered on screen and default size)
-        float[] offset = { -(float)screenWidth / 2, -(float)screenHeight / 2 };
+        float[] offset = { 0, 0 };
-        float zoom = 1.0f;
+        float zoom = startingZoom;
-
-        Vector2 offsetSpeed = new(0.0f, 0.0f);
 
         // Get variable (uniform) locations on the shader to connect with the program
         // NOTE: If uniform variable could not be found in the shader, function returns -1
@@ -63,22 +68,11 @@ public class JuliaSet
         int zoomLoc = GetShaderLocation(shader, "zoom");
         int offsetLoc = GetShaderLocation(shader, "offset");
 
-        // Tell the shader what the screen dimensions, zoom, offset and c are
+        // Upload the shader uniform values!
-        float[] screenDims = { (float)screenWidth, (float)screenHeight };
-        Raylib.SetShaderValue(
-            shader,
-            GetShaderLocation(shader, "screenDims"),
-            screenDims,
-            ShaderUniformDataType.Vec2
-        );
-
         Raylib.SetShaderValue(shader, cLoc, c, ShaderUniformDataType.Vec2);
-        Raylib.SetShaderValue(shader, zoomLoc, zoomLoc, ShaderUniformDataType.Float);
+        Raylib.SetShaderValue(shader, zoomLoc, zoom, ShaderUniformDataType.Float);
         Raylib.SetShaderValue(shader, offsetLoc, offset, ShaderUniformDataType.Vec2);
 
-        // Create a RenderTexture2D to be used for render to texture
-        RenderTexture2D target = LoadRenderTexture(screenWidth, screenHeight);
-
         // Multiplier of speed to change c value
         int incrementSpeed = 0;
         // Show controls
@@ -136,10 +130,19 @@ public class JuliaSet
                 Raylib.SetShaderValue(shader, cLoc, c, ShaderUniformDataType.Vec2);
             }
 
+            if (IsKeyPressed(KeyboardKey.R))
+            {
+                zoom = startingZoom;
+                offset[0] = 1f;
+                offset[1] = 1f;
+                Raylib.SetShaderValue(shader, zoomLoc, zoom, ShaderUniformDataType.Float);
+                Raylib.SetShaderValue(shader, offsetLoc, offset, ShaderUniformDataType.Vec2);
+            }
+
             // Pause animation (c change)
             if (IsKeyPressed(KeyboardKey.Space))
             {
-                pause = !pause;
+                incrementSpeed = 0;
             }
 
             // Toggle whether or not to show controls
@@ -148,8 +151,6 @@ public class JuliaSet
                 showControls = !showControls;
             }
 
-            if (!pause)
-            {
             if (IsKeyPressed(KeyboardKey.Right))
             {
                 incrementSpeed++;
@@ -159,36 +160,32 @@ public class JuliaSet
                 incrementSpeed--;
             }
 
-                // TODO: The idea is to zoom and move around with mouse
+            // If either left or right button is pressed, zoom in/out
-                // Probably offset movement should be proportional to zoom level
             if (IsMouseButtonDown(MouseButton.Left) || IsMouseButtonDown(MouseButton.Right))
             {
                 if (IsMouseButtonDown(MouseButton.Left))
                 {
-                        zoom += zoom * 0.003f;
+                    zoom *= zoomSpeed;
                 }
 
                 if (IsMouseButtonDown(MouseButton.Right))
                 {
-                        zoom -= zoom * 0.003f;
+                    zoom *= 1.0f / zoomSpeed;
                 }
 
                 Vector2 mousePos = GetMousePosition();
+                Vector2 offsetVelocity = Vector2.Zero;
 
-                    offsetSpeed.X = mousePos.X - (float)screenWidth / 2;
+                offsetVelocity.X = (mousePos.X / screenWidth - 0.5f) * offsetSpeedMul / zoom;
-                    offsetSpeed.Y = mousePos.Y - (float)screenHeight / 2;
+                offsetVelocity.Y = (mousePos.Y / screenHeight - 0.5f) * offsetSpeedMul / zoom;
 
-                    // Slowly move camera to targetOffset
+                // Apply move velocity to camera
-                    offset[0] += GetFrameTime() * offsetSpeed.X * 0.8f;
+                offset[0] += GetFrameTime() * offsetVelocity.X;
-                    offset[1] += GetFrameTime() * offsetSpeed.Y * 0.8f;
+                offset[1] += GetFrameTime() * offsetVelocity.Y;
-                }
-                else
-                {
-                    offsetSpeed = new Vector2(0.0f, 0.0f);
-                }
 
                 Raylib.SetShaderValue(shader, zoomLoc, zoom, ShaderUniformDataType.Float);
                 Raylib.SetShaderValue(shader, offsetLoc, offset, ShaderUniformDataType.Vec2);
+            }
 
             // Increment c value with time
             float amount = GetFrameTime() * incrementSpeed * 0.0005f;
@@ -196,13 +193,6 @@ public class JuliaSet
             c[1] += amount;
 
             Raylib.SetShaderValue(shader, cLoc, c, ShaderUniformDataType.Vec2);
-            }
-            //----------------------------------------------------------------------------------
-
-            // Draw
-            //----------------------------------------------------------------------------------
-            BeginDrawing();
-            ClearBackground(Color.Black);
 
             // Using a render texture to draw Julia set
             // Enable drawing to texture
@@ -216,6 +206,11 @@ public class JuliaSet
             DrawRectangle(0, 0, GetScreenWidth(), GetScreenHeight(), Color.Black);
             EndTextureMode();
 
+            // Draw
+            //----------------------------------------------------------------------------------
+            BeginDrawing();
+            ClearBackground(Color.Black);
+
             // Draw the saved texture and rendered julia set with shader
             // NOTE: We do not invert texture on Y, already considered inside shader
             BeginShaderMode(shader);
@@ -229,6 +224,7 @@ public class JuliaSet
                 DrawText("Press KEYS [1 - 6] to change point of interest", 10, 45, 10, Color.RayWhite);
                 DrawText("Press KEY_LEFT | KEY_RIGHT to change speed", 10, 60, 10, Color.RayWhite);
                 DrawText("Press KEY_SPACE to pause movement animation", 10, 75, 10, Color.RayWhite);
+                DrawText("Press KEY_R to recenter the camera", 10, 90, 10, Color.RayWhite);
             }
 
             EndDrawing();